Purification of tin



' residues being drawn off as required.

excess of tin in the reaction vessel.

uarrse stares rare-tar carries.

JEROME JOHN COLLINS, OF 'W'IN SFORD, ENGLAND.-

PURIEICATION or TIN. I

No Drawing.

To all whom it may concern."

Be it known that I, JEROME J oHN CoLLINs, a subject of the King of Great Britain and Ireland, and resident of Field House, WVinsford, Cheshire, England, have invented certain new and useful Improvements Relating to the Purification of Tin, of which the following is a specification.

This invention has for its objec't to provide a simple and effective process for the puri fication of tin from the impurities, such as bismuth, lead, copper, antimony, arsenic, iron, etc., which are frequently associated therewith. V

In accordance with my invention, the impure tin is placed in a solution of tin chlo ride to which chlorine gas is admitted, the chlorine acting to produce stannic chloride which immediately dissolves tin, so again producing stannic chloride, .whereby a continuous dissolving of the tin by chlorine is effected by way of the tin chloride which is prevented from becoming too concentrated and so crystallizing out or solidifying by the addition of water to the solution.

In one convenient application of my invention, the process is carried out continuously,impure tin in a finely divided form, chlorine gas and water being fed into a reaction vessel containing stannic chloride, the stannous chloride liquor produced and the It is important that there shall always be an With this process, it is only necessary to add'suifi- Specification of Letters Patent. Patented Apr, 25 1922.

Application filed November 1,1920. -Seria11 1'o. 421,068.

cient water toprevent the liquor becoming so concentrated as to cause crystallization in the reaction vessel. The chlorine is fed lntov the vessel at a rate Which isnot suflicientto cause boiling of the'liquid due to the heat.

upon the impure tin. The excess of tin inthe generated during the reaction of the chlorine rides and also the precipitation as'm etal of any bismuth present. Lead chloride which is dissolved by the hot liquid, precipitates In the purification of tin,the improved process of obtaining stannous chloride consisting in admitting'impure tin, chlorine gas and water to a reaction vessel containing tin chloride, and drawing off the liquor from the vessel as the process proceeds, asset fortln In testimony whereof I have signed my name to'this specification.

JEROME JOHN COLLINS.

y 7 reaction vessel causes the precipitation of tllG Chl OIlClGS of I arsenic and antimony as insolubleoX-ychlo-i 

